2009-2014 Cadillac CTS-V Performance Mods Discussion, Crank pulleys are now ready for you guys. in Cadillac CTS-V Series Forum - 2009-2014; Originally Posted by qictrk
I'm definitely in for one, probably the $905 one with 10%. But, i have the automatic ...

Re: Crank pulleys are now ready for you guys.

Originally Posted by qictrk

I'm definitely in for one, probably the $905 one with 10%. But, i have the automatic ECM tune and that will have to be figured out first. What if i ship the ECM to you and you tune it there on an automatic that you have at the shop. Won't that work? Cecil..........

Re: Crank pulleys are now ready for you guys.

Hey Jess,

What kind of HP gains are you seeing between the 5% and 10%? Nothing exact just your best guess. I am concerned about traction and pushing the motor to hard on the 10%. Also is the 10% overkill for someone without your exhaust?

You also mentioned a add on heat exchanger in another thread. Do we need one for these?

Re: Crank pulleys are now ready for you guys.

Originally Posted by CadV

Hey Jess,

What kind of HP gains are you seeing between the 5% and 10%? Nothing exact just your best guess. I am concerned about traction and pushing the motor to hard on the 10%. Also is the 10% overkill for someone without your exhaust?

You also mentioned a add on heat exchanger in another thread. Do we need one for these?

Thx

If I was a betting man, I'd go with 30-40 rwtq increase for the 5% overdrive; you'll DEFINITELY FEEL it. I would NOT bet, however, that going to 10% (by itself) is going to yield a 60-80 rwtq increase, as I believe some inefficiencies begin to rear their ugly head when you get boost levels that high without other modifications.

Granted, take my thoughts with a grain of salt, as I'm not nearly as experienced as many on this forum, especially Jesse, but that's my preliminary guess.

Re: Crank pulleys are now ready for you guys.

Originally Posted by Luna.

If I was a betting man, I'd go with 30-40 rwtq increase for the 5% overdrive; you'll DEFINITELY FEEL it. I would NOT bet, however, that going to 10% (by itself) is going to yield a 60-80 rwtq increase, as I believe some inefficiencies begin to rear their ugly head when you get boost levels that high without other modifications.

Granted, take my thoughts with a grain of salt, as I'm not nearly as experienced as many on this forum, especially Jesse, but that's my preliminary guess.

Jess got 559 rwhp out of swapping the blower pulley.

He had the airbox mod, stock exhaust and tune done at the time. Crank should give us more boost.

I am predicting 560-580 with the 5%. 10% is probably overkill until the fuel stuff is sorted.

Re: Crank pulleys are now ready for you guys.

He had the airbox mod, stock exhaust and tune done at the time. Crank should give us more boost.

I am predicting 560-580 with the 5%. 10% is probably overkill until the fuel stuff is sorted.

I am doing the same as you and going with the 5%.

Aye, I think that makes good sense.

I dynoed at ~470 rwhp stock, then went to ~520 rwhp from a tune alone. That's about 50 rwhp from a tune alone. If Jesse got that much, that would leave the pulley swap generating another 30 rwhp, which seems in the ball-park.

I'll shot-in-the-dark estimate that I'll get 30-40 from the crank pulley and end up around 550-560 from the pulley alone. However, I'm also doing the American Racing headers, and Corsa, exhaust system, as well as Hennessey's cold-air intake, so I'm hoping for a tad more than that.

Jesse--what % overdrive does the 2.55" pulley equate to so we can compare the crankshaft pulley to the 2.55" blower pulley? Thanks!

Originally Posted by 1-2-N-V

Is there a mathematical equation that would nail down peak HP at the crank using 560-580 figures? I love the RWHP but any ideas of the BHP? Or is there only estimates.

Just curious...why interested? The number at the tire seems to be the truly important one.

Most of the time, I see people using 15% losses for the drivetrain and that makes decent sense assuming that 556 as a starting point and what people are seeing at the tires.

Re: Crank pulleys are now ready for you guys.

Hey Luna,

Well you know people like to here the bigger numbers and i like to tell them. When they hear 556 they just about fall over. So why not add it up. Isn't that what Hennessey is doing with his V700 package? That 15% math sounds fairly just as everyone who has put up their numbers has seen similar RWHP with just a tune or some kind of combo. If that figure is correct 556BHP x 15% = 473 RWHP

I dynoed at ~470 rwhp stock, then went to ~520 rwhp This would equate to about 612 HP if you ad back the 15%. Add a pulley and you could be looking at around that 700 magic number. All the other breath better goodies, Heads and cam should should easily take you there. No doubt.

Just curious...why interested? The number at the tire seems to be the truly important one.

Most of the time, I see people using 15% losses for the drivetrain and that makes decent sense assuming that 556 as a starting point and what people are seeing at the tires.[/QUOTE]

Re: Crank pulleys are now ready for you guys.

Just to help also on this. The cars are VERY different when you dyno them cold vs hot, vs different intake air temps, vs time running before floored. This could account for people gaining more power from tunes vs others...

This is a motor, just like any other motor. Timing can only be so high, and fuel can only go so lean before you have problems....

If you watch all my dyno vids, the car is run on the rollers until the car hits EXACTLY the same coolant temp, which in my case is 180degrees, And the same intake air charge temps. Sometimes it takes 5 minutes of running on the rollers to hit that... THEN WE DO A PULL. If you just do a startup and then dyno pull after sitting for 3 hours, your horsepower goes up, but only for the dyno and not real world conditions.. REAL world conditions are you driving down the highway and or thru the city and letting some poor sap with a m5 get his feeling hurt as you show him he paid too much for his car.... If you do a pull in our cars when they are completely cold, of coarse you will make alot more power on the dyno, but when is it really going to be that way when you are on the street...

If you look at timing tables, based on coolant, and intake air, you can see that they are able to apply alot more timing during that time. To be fair for horsepower gains, you need to have exact coolant temps, and exact intake 2 temps.. Then it is a fair honest gain.....